Rooms
In the Binding of Isaac, the dungeon structure is randomly generated. However, there are four rooms which are always present in the first 3 chapters: the boss room, the item room, the shop, and the secret room. In The Womb levels, there is only the boss room and the secret room in every level. Occasionally, there is also a challenge room, arcade, and/or mini-boss room. Room Layout The room consists of anywhere from one to four doors, rocks, poop, enemies, fire, pits, chests, and items. (example room layouts?) Rooms can be either "puzzle" rooms, where the player can navigate obstacles to get items, or "battle" rooms, where the player must defeat enemies before being allowed to leave (often a heart, coin, key, bomb, or, rarely, a troll bomb will spawn in the center of the room after defeating all of the enemies). The layouts of the rooms are randomly generated, with different amount of enemies (as well as different positions), rocks (as well as different types of rocks), chests, and items. The item room, shop, boss room, challenge room, arcade, and miniboss room have only one normal room adjecant to them. Item Room The item room (sometimes called the treasure room) is an enemy-less room, with an item in the center of the room on a pedestal. One appears on every level before The Womb. The item room will require a key on every level other than the first, or 2 bombs if the secret room borders the item room. The item room is indicated by a golden rimmed door frame on player view as well as a gold crown on the map. Shop Room To enter this room, a player must use a key, or 2 bombs if the shop borders the secret room. In this room, players can buy a number of Items from a hanged man. Prices are 3 pennies for Hearts, 5 pennies for bombs, keys, faith hearts, pills, and tarot cards, and 15 for Permanent/Collectable and Space/Activated items. Occasionally, items are half price, in which case their price will be in red. The shopkeeper will sell items for hearts on rare occasions like the Devil Rooms; however, the items won't cost anything despite the heart price shown. The shop always requires a key to enter. The "sin" mini-boss Greed will sometimes appear in a shop, replacing the shop on that level even after defeat. Small Hanged Man.png|Hanged Man Without Head Hanged Man.png|Hanged Man Hanged Man No Legs.png|Hanged Man No Legs Shops frequently stock the Ladder, the Batteries, the Steam Sale, The Book of Relevations, the Treasure Map, and the Compass. Other items do appear, but unreliably. Occasionally, a Shop may switch one item for another in a second visit. This may be a bug. (Red price items can be swapped immediately after completing the challenge room.) Shops can only contain two of the same usable item with the rosary (ie:bible). Beggar Room icon on the map.]] The Beggar Room is a randomly occurring room containing the beggar NPC. The room appears as a slot machine icon on the map, as the beggar is like the Slot Machine in that he is a game of chance. Bumping into him costs a penny and gives a chance for the beggar to randomly produce a key, bomb, troll bomb, heart, soul heart, or item. This can can be repeated until he drops an item after which he will blast off through the ceiling. The Beggar will remain until he drops an item or is blown up by a bomb. Beggars can be killed with bombs and will drop random pickup items. It is possible for multiple beggars to exist in the same level, through uses of the Tarot card Judgement or just by chance. Boss Room To escape each level (unless using "We Need to Go Deeper"), the player must travel to the boss room and defeat the boss. The boss room is indicated with a skull above the doorway as well as a skull icon in the minimap. The boss drops items (depending on the boss, either a single stat boosting item (common bosses), item unique to that particular boss (alternate bosses, horsemen) or a devil room item (The Fallen)), 1 to 3 health pickups (depends if "Everything Terrible" is unlocked and if the monster has an alternate color), and the trapdoor to the next floor. Larry Jr intro.png|The into that appears when you enter Larry Jr's boss room. Larry Jr.png|The Larry Jr. Boss Fight Sometimes, a door to the devil room will also appear. Beware that it is possible to go down the trapdoor before collecting the dropped items, especially if Isaac is close to the area where the trapdoor appears when he defeats the boss. Challenge Room The challenge room, also refered to as the "mob trap room", can be recognized by the Gauntlet Door (a pair of crossed swords above the doorway). It can only be entered if the player is at full health (or the equivalent of full health, made up with Soul Hearts), or has the item "The Nail" or "Lord of the Pit". It is also possible to enter the challenge room without full health if it borders a secret room and you blow up the wall in the seret room that leads to the challenge room; however, you can't use bombs to exit the gaunlet room until you have finished it. Once inside the player will find a chest or an item. Upon opening the chest or picking up the item, the player will have to defeat three waves of enemies before being able to exit the room, and like "battle rooms," a heart, coin, key, bomb, pill, or tarot card may spawn in the center after defeating all enemies. This room can appear from the second level onwards. Note: You can spawn all three waves at the same time by pressing pause immediately after taking the loot from the room. This will also happen if you unlock something just as the waves are going to spawn - for example, you open a chest and pick up a coin to give you 55 coins, thus unlocking Cain. As the "You've Unlocked Cain" message appears, all three waves spawn immediately. The Arcade The Arcade contains three games for the players to gamble and play with. Entering the Arcade costs one coin. Inside, players will find a Slot Machine, a Blood Donation Machine, and the Skull Game. An item, such as a coin or a heart, can also spawn upon the first entry. Arcades can appear on every level but the first. *'A Slot Machine:' Players can gamble pennies for a chance to win pills, bombs, keys, hearts, fly items, or more pennies. Sometimes it spawns a fly monster instead. It will eventually break after a number of plays; when it does, it will spawn several items, or the Dollar (set coins to 99). *'A Blood Donation Machine:' Players can exchange life for a random amount of coins. Each transaction costs half a heart, except on "The Womb", where it costs a full heart. It also breaks after a number of usages; it may spawn the Blood Bag item upon breaking. Note: The My Little Unicorn, The Chariot, the Book of Shadows, and the Game Kid items allow you to use the Blood Donation Machine without losing any hearts. *'Skull Game:' Players can gamble in a game to guess which of the three skulls an item is hidden under. Can be a heart (1/2 heart, full heart, soul heart), a bomb (regular, troll, one+), a key, or a special item (skatole). You always win 2 of whatever item was shown (except the skatole). Losing releases a fly to attack the player. The skull swapping animation is always the same, so you have a 33% chance to win. *By destroying any of these with a bomb, random basic items will be released. Mini-Boss Room The player must battle a manifestation of one of the seven deadly sins. The layout for these rooms depends on the sin that is fought. These rooms appear as a skull that is smaller than skulls used to depict boss rooms. You can't bomb your way out of this room, nor can you enter it from the secret room. Secret Room Item]]The Secret Room typically contains no enemies and 3-9 coins (usually pennies, with slight chances for nickels), a slot machine, or an item. The "sin" mini-boss Greed will sometimes appear in a secret room instead - the Compass will show if he resides there. The items that can be found in the secret room are 1UP, Bob's Rotten Head, Book of Belial, Raw Liver, Spider's Bite, Transcendence, Teleport!, and We Need to Go Deeper. Some of these items are more common than others. The room is normally unmarked on the map, although the Treasure Map will show it automatically. The player must bomb the wall of an adjacent room (in the middle, where a door would be) to gain access. X-Ray Vision will automatically reveal entrances and forego the need to bomb, and with the Spelunker's Hat a chime will play when entering such a room, otherwise its location must be guessed. The Secret Room tends to border 3 or 4 normal rooms, a good indication of where to try. Entrances created to the Secret Room close upon leaving it. The player can bomb into other adjacent rooms from inside, but without X-Ray Vision will not be able to enter Boss or Challenge rooms in this manner. Devil Room and Guppy items.]] The Devil Room is available randomly after the player has killed a level boss. There is a higher chance, almost guaranteed to appear if no damage is taken during the boss fight. The room can also be entered randomly when using Teleport! . It behaves like a regular shop, except instead of spending coins, the player can exchange hearts or soul hearts for powerful items. There are only 3 costs for items: 1 heart/3 soul hearts and 2 hearts. Some items only appear in these rooms and don't appear in any treasure room. Once the hearts are spent they cannot be recovered until more heart containers are collected. If you purchase an item which costs your entire HP total, it will reduce you to no HP, and you will die instantly upon taking any further damage. If you purchase an item that costs more than your entire HP total, it will kill you instantly (after the upgrade). It is possible to destroy the rock that the devil is sitting on, allowing the player to pass through him (though this serves no purpose as the devil cannot be killed and so drops no items, money or hearts). Bugs: * if you have hearts and soul hearts and make a purchase that uses all of your regular hearts you will also lose all of your soul hearts. You will then have no hearts shown in the top right but still be alive. * if you have hearts and soul hearts and make a purchase that uses all of your regular hearts you can be killed despite still having soul hearts. * If you have a 1-Up and you make a deal that kills you, you will come back with no heart capacities, and will still be alive, and you will be unable to gain more heart capacities Special Rooms *I am Error